0000000000613415
AUTHOR
Thi Kim Chi Nguyen
Phenolic Acid-Mediated Regulation of the padC Gene, Encoding the Phenolic Acid Decarboxylase of Bacillus subtilis
ABSTRACT In Bacillus subtilis , several phenolic acids specifically induce expression of padC , encoding a phenolic acid decarboxylase that converts these antimicrobial compounds into vinyl derivatives. padC forms an operon with a putative coding sequence of unknown function, yveFG , and this coding sequence does not appear to be involved in the phenolic acid stress response (PASR). To identify putative regulators involved in the PASR, random transposon mutagenesis, combined with two different screens, was performed. PadR, a negative transcriptional regulator of padC expression, was identified. padR is not located in the vicinity of padC , and the expression of padR is low and appears const…
New attenuated strains of apicomplexa and their use as antigen vectors for the prevention of infectious diseases
The present invention concerns a mutant strain of Sarcocystidae in which the two genes mic1 and mic3 are deleted, containing two specific recombination sites of an enzyme enabling a specific recombination in particular Cre recombinase, said specific recombination sites being at the respective locus of each of the above-said deleted genes, the specific recombination site of the enzyme enabling a specific recombination, in particular of Cre recombinase, at the locus of the deleted mic1 gene being different from that at the locus of the deleted mic3 gene.
Genetic and Biochemical Analysis of PadR-padC Promoter Interactions during the Phenolic Acid Stress Response in Bacillus subtilis 168
ABSTRACT Bacillus subtilis 168 is resistant to phenolic acids by expression of an inducible enzyme, the phenolic acid decarboxylase (PadC), that decarboxylates these acids into less toxic vinyl derivatives. In the phenolic acid stress response (PASR), the repressor of padC , PadR, is inactivated by these acids. Inactivation of PadR is followed by a strong expression of padC . To elucidate the functional interaction between PadR and the padC promoter, we performed (i) footprinting assays to identify the region protected by PadR, (ii) electrophoretic mobility shift assays (EMSAs) with a modified padC promoter protected region to determine the interacting sequences, and (iii) random mutagenesi…
Genetic and biochemical characterization by random and site-directed mutagenesis, repressors involved in stress response phenolic acids in Bacillus subtilis
The aim of this work was to characterize the genetic and biochemical mechanisms involved in the PASR, the phenolic acid stress response induced by phenolic acids Bacillus subtilis. By genetics and molecular biology strategies, like reverse genetic, PCR or transposon random mutagenesis, gene deletion, complementation of strains, and gene expression, the main components of the PASR were identified and quantified. Site-directed and random mutagenesis of respectively the promoter of padC encoding the phenolic acid decaroxylase, and PadR, the repressor of the padC expression, allowed us to identify the site of binding of PadR with this promoter, as well as the amino-acid residues involved in the…